Conventionally, there has been known a technique to provide, on a contacted surface such as a touch panel, a realistic tactile sensation to a contact object such as a finger (for example, see PLT 1). In the technology disclosed in the PLT 1, a piezoelectric element is commonly used as a load sensor for detecting pressing (depression) to the contacted surface and also as an actuator for vibrating the contacted surface. When the piezoelectric element functions as the load sensor and detects a predetermined load (output voltage) generated by a pressing operation of the contact object to the contacted surface, the piezoelectric element is controlled to function as the actuator for a predetermined period of time and to vibrate the contacted surface. Similarly, upon detection of the predetermined output voltage generated by a releasing operation of the contact object from the contacted surface, the piezoelectric element is controlled to function as the actuator for a predetermined period of time and to vibrate the contacted surface.